Drug Monograph

Candesartan (Atacand)

candesartan cilexetil

Angiotensin II Receptor Blocker (ARB) · Oral
Pharmacokinetic Profile
Half-Life
~9 hours
Metabolism
Minor hepatic (CYP2C9)
Protein Binding
>99%
Bioavailability
~15%
Volume of Distribution
0.13 L/kg
Clinical Information
Drug Class
ARB
Available Doses
4, 8, 16, 32 mg tablets
Route
Oral
Renal Adjustment
Generally not required; use caution in severe impairment
Hepatic Adjustment
Consider lower dose in moderate impairment
Pregnancy
Contraindicated (Fetal Toxicity)
Lactation
Discontinue drug or nursing
Schedule
Prescription only (not controlled)
Generic Available
Yes
Black Box Warning
Yes — Fetal Toxicity
Rx

Indications

IndicationApproved PopulationTherapy TypeStatus
HypertensionAdultsMonotherapy or combinationFDA Approved
HypertensionChildren 1 to <17 yearsMonotherapy or combinationFDA Approved
Heart failure (NYHA class II–IV)Adults with LVEF ≤40%Adjunctive to standard therapyFDA Approved

Candesartan is a widely used angiotensin II receptor blocker indicated for blood pressure reduction in adults and paediatric patients aged one year and older. Lowering blood pressure with candesartan reduces the risk of fatal and non-fatal cardiovascular events, primarily stroke and myocardial infarction. In heart failure, the CHARM programme demonstrated that candesartan reduces cardiovascular death and heart failure hospitalisations when added to standard therapy, including ACE inhibitors and beta-blockers.

Off-Label Uses

Migraine prophylaxis (8–16 mg once daily): Supported by two randomised controlled trials and a large phase 2 trial (Lancet Neurol 2025), demonstrating comparable efficacy to propranolol in reducing migraine days. Recognised in several European headache guidelines. Evidence quality: Moderate.

Diabetic nephropathy / microalbuminuria reduction: ARBs as a class are used to reduce proteinuria in patients with type 2 diabetes and hypertension; candesartan has been studied in several trials for this purpose. Evidence quality: Moderate.

Dose

Dosing

Adult Dosing

Clinical ScenarioStarting DoseMaintenance DoseMaximum DoseNotes
Hypertension — initial monotherapy16 mg once daily8–32 mg/day32 mg/dayCan be given once daily or split BID. Most BP effect seen within 2 weeks; full effect at 4–6 weeks at a given dose.
May administer with or without food
Hypertension — volume-depleted or diuretic-treated patient8 mg once daily8–32 mg/day32 mg/dayCorrect volume depletion before initiating if possible; start lower to avoid symptomatic hypotension
Heart failure — NYHA class II–IV (LV systolic dysfunction)4 mg once dailyTarget 32 mg once daily32 mg/dayDouble dose every 2 weeks as tolerated toward target of 32 mg once daily. Monitor BP, potassium, and creatinine at each titration step
Can be used alone or added to ACE inhibitor (FDA PI)
Migraine prophylaxis (off-label)8 mg once daily8–16 mg once daily16 mg/dayAllow 8–12 weeks for effect assessment; may titrate to 16 mg if inadequate response at 4 weeks

Paediatric Dosing (Hypertension Only)

Clinical ScenarioStarting DoseMaintenance DoseMaximum DoseNotes
Children 1 to <6 years0.20 mg/kg/day0.05–0.4 mg/kg/day0.4 mg/kg/dayOral suspension available (1 mg/mL); give in 1–2 divided doses
Children 6 to <17 years (<50 kg)4–8 mg/day2–16 mg/day16 mg/dayGive in 1–2 divided doses
Children 6 to <17 years (≥50 kg)8–16 mg/day4–32 mg/day32 mg/dayGive in 1–2 divided doses
Clinical Pearl — Heart Failure Titration

In the CHARM programme, the target dose was 32 mg once daily, and clinical benefit was dose-dependent. Aim for the highest tolerated dose rather than settling at a low dose. In clinical practice, the most common barriers to up-titration are hypotension, rising creatinine, and hyperkalaemia; monitor closely at each doubling step.

PK

Pharmacology

Mechanism of Action

Candesartan cilexetil is an orally active prodrug that is rapidly and completely hydrolysed by esterases in the gastrointestinal wall during absorption to release candesartan, the active moiety. Candesartan binds selectively and with high affinity to the angiotensin II type 1 (AT1) receptor in an insurmountable (non-competitive) fashion, meaning its blockade persists even in the presence of rising angiotensin II levels. By preventing AT1 receptor activation, candesartan inhibits angiotensin II–mediated vasoconstriction, aldosterone secretion, sympathetic nervous system activation, and sodium reabsorption. The AT2 receptor, which may mediate vasodilatory and antiproliferative effects, remains unblocked, potentially contributing to additional cardiovascular benefits. Candesartan does not inhibit ACE (kininase II), so it does not promote bradykinin accumulation — explaining the lower incidence of dry cough compared with ACE inhibitors.

ADME Profile

ParameterValueClinical Implication
AbsorptionAbsolute bioavailability ~15%; Tmax 3–4 h; food does not affect bioavailabilityCan be taken regardless of meals; low bioavailability due to incomplete absorption of the prodrug, not first-pass metabolism
DistributionVd 0.13 L/kg; protein binding >99%; does not cross the blood–brain barrier significantlyHighly protein-bound: unlikely to be displaced by other drugs at therapeutic concentrations; low Vd reflects confinement to plasma compartment
MetabolismMinor hepatic O-deethylation via CYP2C9 to inactive metabolite CV-15959; prodrug hydrolysis is non-CYPLow CYP interaction potential; hepatic impairment increases exposure (AUC +30% mild, +145% moderate)
Eliminationt½ ~9 h; ~67% faeces (via bile), ~33% urine; predominantly excreted unchanged; not removed by haemodialysisOnce-daily dosing adequate for 24-hour coverage; dual elimination pathway means renal impairment alone has moderate impact on clearance
SE

Side Effects

The overall adverse event profile of candesartan in hypertension trials was comparable to placebo. Data below are from placebo-controlled hypertension trials (candesartan n=2,350; placebo n=1,027) and the CHARM heart failure programme (candesartan n=3,803; placebo n=3,796) per the FDA prescribing information.

≥10% Very Common (Heart Failure Population)
Adverse EffectIncidenceClinical Note
Hypotension18.8% (vs 9.8% placebo)In CHARM HF population; dose-related, usually at initiation or titration; more common in patients on high-dose diuretics or combined RAS blockade
1–10% Common
Adverse EffectIncidenceClinical Note
Upper respiratory tract infection6% (vs 4% placebo)Most frequent event in hypertension trials; generally mild and self-limiting
Dizziness4% (vs 3% placebo)May be related to blood pressure reduction; advise caution when driving initially
Back pain3% (vs 2% placebo)Mechanism unclear; not dose-dependent
Pharyngitis2% (vs 1% placebo)Mild; no specific management required
Rhinitis2% (vs 1% placebo)Self-limiting; typically does not warrant discontinuation
Headache~3% (similar to placebo)Not clearly above placebo in most analyses; led to withdrawal in only 0.6% of patients
Hyperkalaemia (HF population)9.5% (vs 3.5% placebo)In CHARM programme (patients on ACE inhibitors); monitor potassium regularly, especially with concomitant potassium-sparing agents
Increased serum creatinine (HF population)7.1% (vs 3.5% placebo)Led to study drug discontinuation in the CHARM trials; expected pharmacological effect of RAS blockade in pre-renal states
Serious Serious (Regardless of Frequency)
Adverse EffectEstimated FrequencyTypical OnsetRequired Action
Fetal toxicityClass effect2nd/3rd trimester exposureDiscontinue immediately upon detection of pregnancy; fetal monitoring
AngioedemaRareAny time during treatmentDiscontinue permanently; emergency airway management if laryngeal involvement
RhabdomyolysisVery rare (post-marketing)VariableDiscontinue; aggressive IV hydration; monitor CK and renal function
Acute renal failureUncommonDays to weeks, especially in volume-depleted patientsHold drug; fluid resuscitation; reassess need for RAS blockade after renal function recovers
Severe hyperkalaemia (>6.0 mEq/L)Uncommon (<1% in HTN; higher in HF)Weeks, especially with dual RAS blockade or renal impairmentDiscontinue or reduce dose; correct potassium; assess concomitant medications; ECG monitoring
Severe hypotension (symptomatic)Uncommon in HTN; 4.2% discontinuation in HFFirst dose or early titrationSupine positioning; IV fluids; consider dose reduction or temporary withholding
Hepatic transaminase elevationRareVariableMonitor LFTs; withdraw drug if elevations persist or worsen (5 patients withdrawn in clinical trials)
Discontinuation Discontinuation Rates
Hypertension Trials
3.3% vs 3.5% placebo
Top reasons: Headache (0.6%), dizziness (0.3%)
Heart Failure (CHARM Programme)
21.0% vs 16.1% placebo
Top reasons: Increased creatinine (7.1%), hypotension (4.2%), hyperkalaemia (2.8%)
Reason for DiscontinuationIncidence (HF)Context
Increased creatinine7.1% vs 3.5% placeboExpected pharmacological effect; often manageable with dose reduction and diuretic adjustment
Hypotension4.2% vs 2.1% placeboMore common in volume-depleted patients or those on high-dose diuretics
Hyperkalaemia2.8% vs 0.5% placeboRisk amplified by concurrent ACE inhibitor, aldosterone antagonist, or impaired renal function
Managing Hyperkalaemia During Candesartan Therapy

In heart failure patients co-prescribed ACE inhibitors and/or aldosterone antagonists, potassium rises are common and expected. Before discontinuing candesartan, consider reducing or stopping potassium supplements and potassium-sparing diuretics, checking for dietary sources, and correcting dehydration. A modest rise in creatinine (up to 30% above baseline) may be tolerable if stable; serial monitoring is essential.

Int

Drug Interactions

Candesartan undergoes only minor CYP2C9-mediated metabolism, and no clinically significant pharmacokinetic drug–drug interactions have been identified with commonly co-prescribed agents. The key interactions are pharmacodynamic, centring on dual RAS blockade, potassium homeostasis, and lithium clearance.

Major Aliskiren (in patients with diabetes or CrCl <60)
MechanismDual RAS blockade at multiple points in the cascade
EffectIncreased risk of hyperkalaemia, hypotension, and renal impairment (ALTITUDE trial terminated early)
ManagementContraindicated in diabetic patients; avoid in CrCl <60 mL/min
FDA PI · ALTITUDE Trial
Major Lithium
MechanismReduced renal lithium clearance via effects on sodium handling in proximal tubule
EffectReversible increases in serum lithium concentrations and potential toxicity
ManagementMonitor lithium levels closely when starting, adjusting, or stopping candesartan; dose adjustment may be needed
FDA PI
Moderate NSAIDs (including COX-2 inhibitors)
MechanismNSAIDs reduce prostaglandin-mediated renal blood flow, opposing the haemodynamic effects of ARBs
EffectAttenuated antihypertensive efficacy; increased risk of acute kidney injury, especially in volume-depleted patients
ManagementMonitor BP and renal function; use shortest course of NSAIDs possible; ensure adequate hydration
FDA PI · Lexicomp
Moderate Potassium-sparing diuretics / K+ supplements
MechanismAdditive effect on potassium retention due to reduced aldosterone activity
EffectIncreased risk of clinically significant hyperkalaemia
ManagementMonitor serum potassium closely, particularly with spironolactone, eplerenone, amiloride, or potassium supplements
FDA PI
Moderate ACE Inhibitors (dual RAS blockade)
MechanismAdditive RAS suppression at two pathway levels
EffectIncreased hyperkalaemia, hypotension, and renal dysfunction; still used together in select heart failure patients under close monitoring (CHARM-Added)
ManagementAvoid routine dual RAS blockade in hypertension; if used in HF, monitor potassium, creatinine, and BP closely
FDA PI · CHARM-Added
Minor Hydrochlorothiazide
MechanismComplementary mechanisms for BP lowering (volume depletion + RAS blockade)
EffectAdditive antihypertensive effect; this is a therapeutic combination (available as fixed-dose combination)
ManagementNo dose adjustment needed; monitor for excess hypotension at initiation
FDA PI
Mon

Monitoring

  • Blood Pressure Each visit; 2–4 weeks after dose change
    Routine
    Assess seated and standing BP at initiation. In heart failure, check for symptomatic hypotension at each titration step. Target per current guidelines (AHA/ACC 2025: <130/80 mmHg for most adults).
  • Serum Potassium Baseline; 1–2 weeks after initiation and each dose increase; then periodically
    Routine
    Essential when co-prescribed with ACE inhibitors, aldosterone antagonists, or potassium supplements. Reduce or stop potassium-sparing agents before escalating dose if K+ trends above 5.5 mEq/L.
  • Renal Function Baseline; 1–2 weeks after initiation and each dose increase; then every 3–6 months
    Routine
    Serum creatinine and eGFR. A rise of up to 30% in creatinine may be tolerated if stable. Worsening renal function in paediatric patients (1 in 93 children aged 1–6; 3 in 240 aged 6–17) was observed in clinical trials.
  • Haemoglobin / Haematocrit Baseline; then as clinically indicated
    Trigger-based
    Mean haematocrit decrease of ~1.6% reported versus 0.9% with placebo. Check if anaemia symptoms develop.
  • Hepatic Function If symptoms of liver injury develop
    Trigger-based
    Five patients were withdrawn from clinical trials due to elevated transaminases. Check ALT/AST if jaundice, nausea, or unexplained fatigue occurs.
  • Pregnancy Status Before initiation and as applicable
    Routine
    Confirm negative pregnancy test in women of childbearing potential before starting. Discontinue as soon as pregnancy is detected (FDA boxed warning).
CI

Contraindications & Cautions

Absolute Contraindications

  • Known hypersensitivity to candesartan cilexetil or any excipient
  • Pregnancy (2nd and 3rd trimesters — FDA boxed warning; avoid throughout pregnancy when possible)
  • Children <1 year of age — drugs acting on the RAS can impair normal renal development
  • Co-administration with aliskiren in patients with diabetes mellitus

Relative Contraindications (Specialist Input Recommended)

  • Bilateral renal artery stenosis or stenosis of a solitary kidney — risk of acute renal failure; ARBs should generally be avoided
  • Severe hepatic impairment (Child–Pugh C) — pharmacokinetics not studied; use with extreme caution
  • Severe renal impairment (CrCl <30 mL/min) — increased drug exposure and higher risk of hyperkalaemia; maximum 8 mg/day may be appropriate per PK data
  • Concomitant dual RAS blockade (ACE inhibitor + ARB) for indications other than specific heart failure protocols — increased risk of adverse outcomes (ONTARGET)

Use with Caution

  • Volume or salt depletion — correct before initiating; consider lower starting dose
  • Elderly patients — higher Cmax (~50%) and AUC (~80%) observed; start at usual dose but titrate carefully
  • Patients of Black race — may have reduced antihypertensive response as a low-renin population; consider combination therapy
  • Aortic or mitral valve stenosis / hypertrophic cardiomyopathy — caution with vasodilators
FDA Boxed Warning Fetal Toxicity

Drugs that act directly on the renin–angiotensin system can cause injury and death to the developing fetus when used during the second and third trimesters. Reported fetal complications include oligohydramnios, skull hypoplasia, lung hypoplasia, anuria, hypotension, renal failure, and death. When pregnancy is detected, candesartan should be discontinued as soon as possible.

Pt

Patient Counselling

Purpose of Therapy

Candesartan helps protect the heart and blood vessels by blocking the effects of a hormone called angiotensin II that raises blood pressure and strains the heart. In hypertension, lowering blood pressure reduces the long-term risk of stroke and heart attack. In heart failure, candesartan has been shown to reduce the need for hospital admissions and improve survival.

How to Take

Take candesartan once daily (or as directed), at the same time each day, with or without food. Swallow the tablet whole with water. If using the oral suspension for a child, shake well before each dose. Do not stop taking candesartan without consulting a prescriber, even if you feel well, as high blood pressure often has no symptoms.

Dizziness & Light-headedness
Tell patient Some dizziness may occur during the first few days, especially when standing up quickly. Rise slowly from sitting or lying positions. This often improves as the body adjusts to the medication.
Call prescriber If dizziness is severe, persistent, or associated with fainting. Also report if accompanied by reduced urine output.
Pregnancy & Contraception
Tell patient Candesartan can cause serious harm or death to an unborn baby, particularly in the second and third trimesters. Women of childbearing potential should use reliable contraception throughout treatment.
Call prescriber Immediately if pregnancy is suspected or confirmed — the medication must be stopped as soon as possible.
Potassium-Rich Foods & Supplements
Tell patient Avoid using potassium supplements, salt substitutes containing potassium, or excessive high-potassium foods without medical advice, as the medication can raise blood potassium levels.
Call prescriber If muscle weakness, slow or irregular heartbeat, or tingling sensations develop, as these may signal elevated potassium.
Dehydration & Illness
Tell patient Vomiting, diarrhoea, excessive sweating, or not drinking enough fluids can lower blood pressure further while on candesartan. Stay well hydrated, especially in hot weather or during illness.
Call prescriber If prolonged vomiting, diarrhoea, or reduced urine output occurs, as this may require temporary dose adjustment.
Swelling of Face, Lips, or Throat
Tell patient Angioedema (swelling of the face, lips, tongue, or throat) is rare but can be serious. It can occur at any point during treatment.
Call prescriber Seek emergency medical attention immediately if swelling of the face, lips, tongue, or throat occurs, or if difficulty breathing develops.
Ref

Sources

Regulatory (PI / SmPC)
  1. Atacand (candesartan cilexetil) tablets — FDA-approved prescribing information. ANI Pharmaceuticals, Inc. Revised 2020. FDA Label Primary regulatory source for all approved indications, dosing, contraindications, and adverse event rates cited in this monograph.
  2. Candesartan cilexetil tablets — DailyMed prescribing information. U.S. National Library of Medicine. DailyMed Current DailyMed listing providing updated labelling information including paediatric dosing and oral suspension preparation.
Key Clinical Trials
  1. Pfeffer MA, Swedberg K, Granger CB, et al. Effects of candesartan on mortality and morbidity in patients with chronic heart failure: the CHARM-Overall programme. Lancet. 2003;362(9386):759–766. DOI Overall CHARM analysis demonstrating the broad benefit of candesartan across the spectrum of heart failure, including the 9% reduction in all-cause mortality.
  2. McMurray JJV, Ostergren J, Swedberg K, et al. Effects of candesartan in patients with chronic heart failure and reduced left-ventricular systolic function taking ACE inhibitors: the CHARM-Added trial. Lancet. 2003;362(9386):767–771. DOI Demonstrated 15% relative risk reduction in CV death or HF hospitalisation when candesartan was added to ACE inhibitors.
  3. Granger CB, McMurray JJV, Yusuf S, et al. Effects of candesartan in patients with chronic heart failure and reduced left-ventricular systolic function intolerant to ACE inhibitors: the CHARM-Alternative trial. Lancet. 2003;362(9386):772–776. DOI Key evidence supporting candesartan as first-line RAS blockade in heart failure patients who cannot tolerate ACE inhibitors.
  4. Yusuf S, Pfeffer MA, Swedberg K, et al. Effects of candesartan in patients with chronic heart failure and preserved left-ventricular ejection fraction: the CHARM-Preserved Trial. Lancet. 2003;362(9386):777–781. DOI Evaluated candesartan in HFpEF; showed trend toward benefit and significant reduction in heart failure hospitalisations.
  5. Young JB, Dunlap ME, Pfeffer MA, et al. Mortality and morbidity reduction with candesartan in patients with chronic heart failure and left ventricular systolic dysfunction. Circulation. 2004;110(17):2618–2626. DOI Pooled CHARM low-LVEF analysis confirming an 18% reduction in combined CV death or HF hospitalisation and 12% reduction in all-cause mortality.
Guidelines
  1. Heidenreich PA, Bozkurt B, Aguilar D, et al. 2022 AHA/ACC/HFSA guideline for the management of heart failure. J Am Coll Cardiol. 2022;79(17):e263–e421. DOI Current US heart failure guideline positioning ARBs including candesartan in patients intolerant to ACEi/ARNI.
  2. Jones DW, Ferdinand KC, Taler SJ, et al. 2025 AHA/ACC guideline for the prevention, detection, evaluation, and management of high blood pressure in adults. J Am Coll Cardiol. 2025;86(18):1567–1678. PubMed Most current US hypertension guideline; includes ARBs as first-line agents for blood pressure control.
Migraine Evidence
  1. Tronvik E, Stovner LJ, Helde G, et al. Prophylactic treatment of migraine with an angiotensin II receptor blocker: a randomized controlled trial. JAMA. 2003;289(1):65–69. DOI First RCT demonstrating candesartan 16 mg reduces migraine days compared to placebo.
  2. Stovner LJ, Linde M, Gravdahl GB, et al. A comparative study of candesartan versus propranolol for migraine prophylaxis. Cephalalgia. 2014;34(7):523–532. DOI Confirmed candesartan is non-inferior to propranolol for migraine prevention with a different side-effect profile.
  3. Øie LR, Wergeland T, Salvesen Ø, et al. Candesartan versus placebo for migraine prevention in patients with episodic migraine: a randomised, triple-blind, placebo-controlled, phase 2 trial. Lancet Neurol. 2025;24(10):817–827. DOI Largest multicentre trial to date (n=457); both 8 mg and 16 mg reduced monthly migraine days versus placebo.
Pharmacokinetics / Special Populations
  1. Hubner R, Hogemann AM, Sunzel M, Riddell JG. Clinical pharmacokinetics of candesartan. Clin Pharmacokinet. 2002;41(1):7–17. DOI Definitive PK review establishing bioavailability, volume of distribution, protein binding, and half-life parameters used in this monograph.
  2. Kassem M, Bhatt HM, Gala T, et al. Population pharmacokinetics of candesartan in patients with chronic heart failure. Clin Transl Sci. 2021;14(3):1012–1021. DOI Pop-PK study identifying weight, eGFR, and diabetes as significant covariates affecting candesartan clearance in heart failure patients.